The aims are to evaluate the safety and efficacy of 1,3,6, and 9 million IU of PEG-Interferon alfa-2a administered subcutaneously once a week and 3 million IU two to three times per week for 24 weeks compared to thrice-weekly treatment with 3 million IU Roferon-A in the treatment of chronic hepatitic C. A further aim is to determine the best dose and regimen of PEG-IFN-alfa-2A in the treatment of chronic hepatitis C.